Accelerator for the vulcanization of rubber.



cnARn s REID BOGGS, or ARLmqToN HEIGHTS, mAssAcnu'sETTs, AssIeNoR To smrmax WIRE & CABLEUQ, or BOSTON, MASSACHUSETTS, A CORPORATION or MASSACHUSETTS.

' AccELERAToR FOR THE VULCANIZATION or RUBBER.

No Drawing:

To all whom it may concern:

Be it' known that I, CHAnnEs REID Bose-s,

, a citizen 6f the United States, and resident of Arlington Heights, in the county of Middle sex and State 'of Massachusetts, have invented an Improvement in Accelerators for the vulcanization of Rubber, of which the I plantation rubbers, as well as with reclaimed following description is a specification.

In the process of vulcanizing rubber, 'it 1s important ,that the rubber either havp contained therein sufiicient mineral or-organic matter to hasten and assist. the vulcainzing process, or that some mixture whichwill act as an accelerating agent during the vulcanizing process be employed. Also the addrtion of some acceleratingagent isusually desirable to hasten the vulcanization and to improve the resulting product. Thisuse of an accelerator is particularly important in the caseof the lower grades of-wi-ld and or regenerated rubber. Furthermore; in the vulcanization of synthetic or artificial rubher and its homologues, it is of courselnecessary and important to add an acceleratorto assist inthe vulcanization-of this type of rubber, as 'synthetic rubber, from its method of manufacture, is practically a pure rubber product and is entlrely free from those impurities impregnating the best wild rubber, which natural impurities or fillers act as accelerators.

I have discovered that vulcanized rubber and the. products made therefrom are greatly ture, such for example as para-phenylenediamin, and 'beta-naphthylamin, or their reacting compounds. I have also discovered that the action of such accelerators is effective whether sulfur, selenium, as set forth in y types of, vulcanizing agents are used, and

Specification of Letters Patent.

coendifig application Serial 'NoQ 824,951, led arch 16,1914, or any presentthese accelerators may be employed with equal advantage whether hard or soft vulcanized rubber is being made. While I have successfully employed such primary and secondary amins as accelerators on various grades of rubber, with equal success, I am not, at present, positive that they also act as catalyzers. However, I believe that the action is not only'somewhat catalytic inrespect to the vulcanization, but also has an effect on the degree of polymerization of the rubber.

This theory is further substantiated by the fact that heat applied either externally or internally by other means does not, produce the same result.

active vulcanizing accelerators; or their re- Patented Mar. 4, 1919; Application filed flarch 16, 1914. Serial No. 824,950;

These amins may be the action products may constitute the actual vulcanizing accelerator with sulfur or other vulcanizing agent in the rubber, together with a hydrogen sulfid absorberysuch for example as litharge. However, I also find that in many cases,,litharge has no appreciable eflect, and therefore do not wish to be understood as being limited to' either use or omit such an'absorber.

In practice, I find that the resulting product, whether hard or soft vulcanized rubber, is greatly improved as to all the physical tests and lasting qualities, such physical tests being as to tensile strength, elasticity, resiliency, and the lasting qualities or life of the rubber product. I Furthermore, I have discovered that the use of these amins substantially prevents, or greatly lessens, the amount of depolymerization of the rubber product, when subjected to heat or a similar depolymerizative agent. I believe it to be a distinct novelty in the art of rubber vulcanization to use primary or. secondary amins of thealiphatic or aromatic series, or other rin structures, as above ex plained, as an aqce eratorfor the vulcanization of rubber, and I therefore wish to claim the same broadly. Also the use of these so I amins materially shortens the time hereto fore required, for vulcanization, while producing an equally valuable'product, or increases the physical tests and enduring quali ties of the product where the time andtemperature of vulcanization as ordinarily practised is the same. y

In carrying out my invention, I have found that a wide range of proportions and con.-

stituent's may be employed, but the following have been found especially practicable and whiting and zinc oxid are inert materials, it-

makes but little difference in what proportions they are used, although I find-a suitable admixture, is 140 parts of whiting and parts of zinc, making a total of 190 parts, as above mentioned. This mixture willtest as well as a similar Para rubber compound,

and will show an increase of 47% of the. tensilestrength and 11% of the ultimate elongation when compared with the same-compound without the accelerator.

The above compound made with a low grade of plantation hevea rubber, in place of thepontianak, will test as well as a similar Para rubber compound, and will show an increase of 30% of the tensile strength and 17% of the "ultimate elongation when compared with the samecompound without the acceleratoii" 4 It will. be understoodthat I do not mean to limitmy invention to the particular formula or kinds of rubber above mentioned,

but wish it understood that I may apply the same to any of the wide variety of mixtures Also the accelerators I have explained above maybe advantageously employed with the different mineral and organic fillers in the rubber as well as in the vulcanization of synthetic rubber. Furthermore a mixture of my accelerators with other sorts of accelerators may be employed satisfactorily resulting 1n a greatly improved vulcanized product.

In the present application I have explained both my process and the agent utilized therein, and wish to claim the agent and the resulting product, reserving the claims on the process for a divisional application.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

As an article of manufacture, vulcanized rubber containing before vulcanization rubber and beta-napthylamin.

In testimony whereof I have signed my name to this specification in the presence of two 'subscribin witnesses.

'C LES-REID BOGGS. Witnesses:

HENRY WAITE BionLow, AGNES BERNIGE Gmrnv. 

